This invention relates to polarographic cells including a silver/silver chloride reference electrode.
In polarographic cells having two electrodes, one electrode is polarized in the presence of the substance being measured and is known as the sensor electrode. The second electrode is depolarized in the presence of the substance being measured and is known as the reference electrode. An electrolyte generally provides an electrical path between the two electrodes, which otherwise are in an electrically insulating relation. In the presence of the substance being measured a current passes between the electrodes, the current being, at a given applied voltage, proportional to the concentration of the substance. The voltage applied to the cell is the potential of the sensor relative to that of the reference electrode; the potential of the reference electrode should therefore be constant. The current passing between the electrodes may result in undersirable potential changes at the reference electrode. To counter this effect a third, counter, electrode is often used so that the current generated will pass between the sensor and counter electrode.